We have received many enthusiastic comments since the release of the spatial analysis tools in Map Viewer. Some of you also asked us questions about online analysis in general, as well as the differences in the tools between Map Viewer and Map Viewer Classic. Today’s blog post serves as an FAQ for information about analysis in Map Viewer.
Are there different tools in Map Viewer Classic and Map Viewer?
Yes. The initial release of analysis in Map Viewer includes 22 feature analysis tools and 24 raster analysis tools. Some of the tool names have been updated in Map Viewer to better reflect their capabilities. For example, the Create Drive-Time Areas tool in Map Viewer Classic has been renamed to Generate Travel Areas in Map Viewer. There are also two new raster analysis tools (see below). For now, seven tools are available only in Map Viewer Classic. The outstanding analysis tools and functionality will migrate to Map Viewer in future releases.
See the online documentation for the most up-to-date list of tools that have been renamed, and the list of tools that are available in Map Viewer.
Are there any new tools in Map Viewer that are not available in Map Viewer Classic?
Yes! Two brand new raster analysis tools have been added in the Map Viewer that did not exist in Map Viewer Classic: Surface Parameters and Derive Continuous Flow in the Analyze Terrain group (available with the ArcGIS Image for ArcGIS Online user type extension).
Can I still use Living Atlas Layers such as administrative boundaries for analysis?
Yes! ArcGIS Living Atlas feature layers are supported. In the initial release, data must be added to the web map in order to be used in analysis tools. We will support the capability to choose analysis layers from within a tool in upcoming releases.
What are the best sources of imagery layers to use in the raster analysis tools?
The best source of imagery layers for analysis are the imagery layers that you host in your organization through ArcGIS Image for ArcGIS Online. Both tiled and dynamic imagery layers are supported. Note that not all layers from the ArcGIS Living Atlas can be used as input for the raster analysis tools. For some of those Living Atlas layers, it may be a format issue. There may also be additional settings on the specific imagery layer set by the owner that prevent you from using it in analysis. To ensure your data can be used by the tools, create your own hosted imagery layers. Most of the raster analysis tools create a new imagery layer as output, which can be used to continue the analysis or share your results.
Are KML, GeoRSS, or Map Notes supported as analysis input in Map Viewer?
No. For the initial release, only feature layers and tables are supported for feature input. In Map Viewer, sketch layers have replaced map notes in Map Viewer Classic. Analysis tools will support additional data format including sketch layers in an upcoming release. The functionality to interactively draw features from within a tool, such as the point input for Trace Downstream, will also be added in an upcoming release.
Can I analyze a subset of data from the input layer?
Yes! There are two ways to define a subset of data to be used in analysis tools; applying a filter in Map Viewer and specifying a processing extent (see below) in the tool’s environment settings. You can use the Filter option in Map Viewer to set an attribute filter on your input data. When you set a filter on an input feature layer, only those features that meet the filter criteria will be used in the analysis. You can also zoom in to the area you want to analyze, and select “Display extent” from the environment settings of the tool. In this case, only the features or rasters within the visible extent will be analyzed.
Limiting the number of features or raster cells in your analysis can also help reduce the number of credits consumed by the tool.
What extent of my data is used for analysis?
The processing extent is the geographic area of interest to be applied to a tool, in which only features or raster cells inside the extent rectangle will be used in the analysis. In Map Viewer, we have added more ways to set the processing extent. In addition to full extent and the current map display extent, you now also have the option to specify the coordinates that make the four corners of the extent rectangle or use the extent of a specific layer. These new options are available in the environment settings in each tool. The default processing extent in Map Viewer is “full extent”, which typically includes all input features, or the entire raster. The environment settings allow you to set and control parameters such as the processing extent, a coordinate system for analysis output, and raster analysis settings such the resampling method, mask, and cell size of the output raster. These settings are saved in the analysis history for each tool run in your web map.
What projection is used in the ArcGIS Online analysis calculations?
By default, the analysis tools use the original coordinate system of the input layer for calculations. Check out this blog article for more details on analysis in ArcGIS Online and projections. If you would like to set the coordinate system used for analysis, you can now do so in Map Viewer using the output coordinate system parameters in the tool’s environment settings. The output coordinate system sets both the coordinate system for analysis, and the coordinate system for the output layers.
Where is the option to create hosted feature layer view for the Join Features tool?
The option to create a hosted feature layer view based on a join will no longer be available through the Join Features tool. Instead, join views will be added to the updated experience for creating hosted views in an upcoming release
Where is the option to normalize my data by population in the Find Hotspots and Find Outliers tools in Map Viewer?
With the initial release in Map Viewer, you can use the “Divided by field” option in the Find Hot Spots and Find Outliers tools and provide a population field to normalize. The option to divide by population from Esri’s GeoEnrichment service will be added in a future release.
How can I control who can use spatial analysis tools in my organization and limit the number of credits used?
Administrators can create custom roles for members, including privileges to access tools they need to use and to restrict access to tools they do not need. For example, a member may be assigned with a privilege to use Spatial Analysis tools but not to use the Enrich Layer tool. In addition, administrators can use credit budgeting to set a limit of credits that a member can use. As a good practice, we encourage you to always check the required credits prior to running a tool by clicking the Estimate credits button.
I hope the answers provided here are helpful. The web analysis team would like to know what other questions you may have, so please share them with us at the ArcGIS Online Community. As always, we would love to hear your experiences and comments about performing analysis in ArcGIS Online.
Note: an update of the Map Viewer analysis was made available in June 2023. Check here for what’s new.